1. Field
Methods and apparatuses consistent with the exemplary embodiments relate to a broadcast transmitting apparatus, a broadcast receiving apparatus, and a method thereof. More particularly, exemplary embodiments relate to a broadcast transmitting apparatus, which may transmit/receive a digital broadcast, and a broadcast receiving apparatus and a method thereof.
2. Description of the Related Art
In a related art, digital broadcasting has an advantage of providing high definition broadcasting, due to excellent transmission efficiency two-way services, such as a VOD service, etc. Accordingly, in Korea, skywave analogue broadcasting will come to an end in 2013, and will be converted to digital broadcasting. Cable TVs also will convert to digital broadcasting. Further, digital skywave broadcasting adopts ATSC methods, while digital cable broadcasting will be transmitting in a QAM (Quadrature amplitude modulation) method.
However, in the related art, approximately ⅔ of cable broadcasting receivers are analogue cable broadcasting receivers. Thus, in order to convert analogue cable broadcasting receivers to digital cable broadcasting in the related art, it is essential to install set top boxes, etc., and pay expensive subscription fees. Accordingly, in order to expand digital cable broadcasting to low income classes in the related art, a Clear QAM has been introduced. A Clear QAM is a signal which may be transmitted without scrambling. Thus, the clear QAM enables one to view digital cable broadcasting free of charge through a TV where a digital broadcasting receiver is embedded.
However, in a case of transmitting all broadcasting contents or channels by the clear QAM in the related art, there is a problem that a cable operator cannot differentiate service ratings between paid subscribers and free subscribers. Accordingly, there is a need for a method which may differentiate service ratings between paid subscribers and free subscribers, regarding broadcasting signals transmitted by the Clear QAM.